1. Field
Embodiments of the invention relate to power systems for aerial devices. More particularly, embodiments of the invention relate to an isolated electronic backbone architecture for aerial devices.
2. Related Art
Utility workers utilize an aerial device to reach inaccessible locations. The aerial device generally includes a boom with a utility platform connected to a distal end of the boom. One or more utility workers stand in the utility platform to perform a task. Utility workers typically use an aerial device to access overhead electric power lines and electric power components for installation, repair, or maintenance.
The utility platforms utilized by electric utility workers are highly insulated so as to prevent the discharge of electricity through the utility truck, and especially through the utility worker. However, these utility platforms require power to perform various functions and equipment. In order to maintain this insulation, aerial devices of the prior art utilize only hydraulic power or battery power at the utility platform. This presents several problems because hydraulic power is limited in what functions it can perform and is very inefficient, and battery power requires continual replacement and maintenance.
Aerial devices of the prior art are also frequently inefficient. First, the hydraulic power systems of aerial devices are powered by large diesel or gas internal-combustion engines. These engines must operate continuously or nearly continuously during static operations to power the various functions. While some operators can turn the engine off when not necessary, the ratio of hydraulic operation to total engine running time is very inefficient. Similarly, the entire engine must be run even when only a small percentage of the total horsepower is necessary to perform the various functions. Second, there are significant energy losses in valves, manifolds, and lines. For example, pressure drop from a pump to an actuator can be as great as 400 psi in some system designs.